ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2019-07-13
    Description: Breccia 73255 contains sparse small clasts of basalts that have mare affinities; the basalts are members of a single differentiated suite. The clasts have been fractured throughout and locally granulated. Textural and compositional evidence indicates that the fracturing and granulation were produced by the 73255 breccia-forming event, and this event took place before the basalts had completely solidified. Thus, it appears that the eruption of the basalts took place at about the same time as the formation of the 73255 breccia, about 3.9 b.y. ago. The mineral assemblages and modes of the basalt clasts are those typical of mare basalts, but the clasts are not identical in detail with any basalts returned from the mare surfaces. They are instead most similar to the 14053-type basalts from the Apollo 14 site.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar and Planetary Science Conference; Mar 17, 1980 - Mar 21, 1980; Houston, TX
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2019-07-13
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar and Planetary Science Conference; Mar 19, 1979 - Mar 23, 1979; Houston, TX
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2019-07-13
    Description: Laser (Ar-39)-(Ar-40) studies of clasts and groundmass in breccia 73255 are presented. They show a variety of ages indicating that some materials lost argon from sites that outgas at low temperature, while other materials have retained argon generated before the breccia-forming event. The estimate for the time of the breccia-forming event from thermal release studies is compared to the upper limit of the event from the laser studies; this work also shows that ages in excess of 4.0 G.y. determined on rocks containing devitrified maskelynite clasts probably have no chronological significance.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar and Planetary Science Conference; Mar 19, 1979 - Mar 23, 1979; Houston, TX
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2019-07-13
    Description: A study of two clasts of coarse-grained anorthositic-noritic-troctolitic-suite norites from the fragment-laden melt rock 73255 is presented. Both clasts are igneous rocks crystallized from melts that were probably internally generated; clast 27,80 is a cumulate, and the parent magmas of both rocks probably crystallized below the lunar surface. Despite similar history, the parent rocks of the two clasts appear to be derived from distinct magma types: the 27,80 is characterized by plagioclase and orthopyroxene as the major constituents and by a high K, Nb, and Zr content, while the 27,45 type also contains augite and has a low content of K, Nb, and Zr.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar and Planetary Science Conference; Mar 19, 1979 - Mar 23, 1979; Houston, TX
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2019-07-13
    Description: Eleven splits from the mafic-mineral-rich part of anorthosite 60025 were studied in order to establish the exact nature and causes of compositional variations in the minerals of lunar ferroan anorthosites. All splits were analyzed by INAA, and five were studied intensively by petrologic techniques. All splits were found to have similar cataclastic textures and show textural evidence of at least two episodes of deformation. The whole-rock split contains mafic minerals having a wide range of compositions and is probably polymict. It is suggested that the rare-earth patterns for all splits can be duplicated safactorily, assuming that the equilibrium liquids had flat, or nearly flat, chondrite-normalized rare-earth patterns. The plagioclases in all splits were found to be identical. Data obtained indicate that in ferroan anorthosites An content in plagioclase and mg' of associated mafic minerals are not strongly correlated.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar and Planetary Science Conference; Mar 12, 1990 - Mar 16, 1990; Houston, TX; United States
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2019-07-13
    Description: Results of a study of 16 samples from the anorthositic ferroan subgroup, or 'typical' ferroan anorthosites, are reported. The presence of heterogeneous, bimodal, and/or trimodal pyroxene compositions suggests that some of the anorthosites are polymict rocks; however, they are composed entirely of ferroan-anorthosite-suite lithologies. It is suggested that complex processes operated during the formation of the ferroan anorthosites. It is argued that original igneous compositional characteristics were altered during and/or after crystallization. Processes operative during anorthosite formation may have included some mixing of different melts, trapping of variable amounts of intercumulus liquid, postcrystallization redistribution of elements, or perturbations both during adcumulus growth and subsequent to crystallization by impact events.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Journal of Geophysical Research (ISSN 0148-0227); 98; E5; p. 9089-9105.
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2019-07-13
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar and Planetary Science Conference; Mar 17, 1980 - Mar 21, 1980; Houston, TX
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2019-07-13
    Description: A petrologic study of crystalline lithic clasts from feldspathic breccia 67975, collected on the rim of North Ray crater at the Apollo 16 site, is presented. A light gray group has been identified as granulitic breccias, and a dark gray group has been identified as feldspathic microporphyritic melt breccias. It is suggested that complete homogenization of the minerology of the granulitic breccias may have been prevented by their incorporation into the 67975 fragmental breccia, and that metamorphism of the clasts may have been interrupted by this breccia forming event.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar and Planetary Science Conference; Mar 14, 1988 - Mar 18, 1988; Houston, TX; United States
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2019-07-13
    Description: Feldspathic granulite 79215, an annealed polymict breccia which has a bulk composition between anorthositic gabbro and gabbroic anorthosite, contains numerous oxide complexes in the matrix. An Ar-39-Ar-40 stepwise heating experiment gives a well-defined plateau corresponding to an age of 4.03 + or - 0.02 AE. The polmict character of this breccia and the variability of the complexes suggest that they formed as a consequence of reactions between spinel-rich clasts and matrix under the high-T low-P conditions of an ejecta blanket. The duration of annealing is estimated to have been less than 10 million yr; the absence of a KREEP component may indicate an inhomogeneous distribution of this component at the lunar surface at 4.0 AE.
    Keywords: LUNAR AND PLANETARY EXPLORATION
    Type: Lunar and Planetary Science Conference; Mar 13, 1978 - Mar 17, 1978; Houston, TX
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...